<template>
    <div class="city-list" ref="wrapper">
        <div>
            <div class="area">
                <div class="title border-topbottom">当前城市</div>
                <div class="button-list">
                    <div class="button-wrapper">
                        <div class="button">{{this.currentCity}}</div>
                    </div>
                </div>
            </div>
            <div class="area">
                <div class="title border-topbottom">热门城市</div>
                <div class="button-list">
                    <div class="button-wrapper" 
                      v-for="item of hot" 
                      :key="item.id"
                      @click="handleCityClick(item.name)"
                    >
                        <div class="button">{{item.name}}</div>
                    </div>
                </div>
            </div>
            <div 
              class="area" 
              v-for="(item, key) in cities" 
              :key="key"
              :ref="key"
            >
                <div class="title border-topbottom">{{key}}</div>
                <ul class="item-list">
                    <li class="item border-bottom" 
                      v-for="innerItem in item" 
                      :key="innerItem.id"
                      @click="handleCityClick(innerItem.name)"
                    >
                      {{innerItem.name}}
                    </li>
                </ul>
            </div>
        </div>
    </div>
</template>
<script>
import BScroll from 'better-scroll'
import { mapState, mapMutations, mapGetters} from 'vuex'
export default {
  name: 'CityList',
  props: {
    hot : Array,
    cities: Object,
    letter: String
  },
  computed: {
    ...mapState({
      currentCity: 'city'    // vuex中公用数据city，映射到组件的计算属性里，名字是currentCity，组件中使用this.currentCity
    }),
    ...mapGetters(['doubleCity'])
  },
  methods: {
    handleCityClick (city) {
      // console.log(city)
      // this.$store.dispatch('changeCity', city)
      this.changeCity(city)
      this.$router.push('/')
    },
    ...mapMutations(['changeCity'])  // vuex中有一个mutation叫做changeCity，将mutation映射到组件的名字叫changeCity的方法里，组件中使用this.changeCity
  },
  mounted () {
    this.scroll = new BScroll(this.$refs.wrapper)
  },
  watch: {  
      letter () { // 监听letter变化
        if (this.letter) {
          const element = this.$refs[this.letter][0]
          this.scroll.scrollToElement(element)
        }
        // console.log(this.letter)
      }
  }
}
</script>
<style lang="stylus" scoped>
  @import '~styles/varibles.styl'
  .border-topbottom
    &:before
      border-color: #cccccc
    &:after
      border-color: #cccccc
  .border-bottom
    &:before
      border-color: #cccccc
  .city-list
    overflow: hidden
    position: absolute 
    top: 1.58rem
    right: 0
    bottom: 0
    left: 0
  .title 
    line-height: .54rem
    background: #eeeeee
    padding-left: .2rem
    font-size: .26rem
    color: #666666
  .button-list
    overflow hidden
    padding: .1rem .6rem .1rem .1rem
    .button-wrapper
      float: left
      width: 33.33%
    .button
      margin: .1rem
      padding: .1rem 0
      text-align: center
      border: .02rem solid #cccccc
      border-radius: .06rem
  .item-list
    .item
      line-height: .76rem
      padding-left: .2rem
</style>


